Nielsen Hayden genealogy
Descendants of Owain ap Maredudd ab Owain ap Gruffudd
- 1275Father: Maredudd ab Owain ap Gruffudd ab Yr Arglwydd Rhys ( - Mar 1265 Llanbardarn Fawr, Ceredigion, Wales)
Owain ap Maredudd ab Owain ap Gruffudd (of Iscoed, Ceredigion, Wales - 15 Aug 1275 bur.Strata Florida Abbey, Ceredigion, Wales)
   └─ Llywelyn ab Owain ap Maredudd ab Owain (of Cedewain, Powys, Wales - 1309)
   
       └─ Thomas ap Llewellyn ab Owain ap Maredudd (of Iscoed, Ceredigion, Wales - 1343)
        Elinor ferch Maredudd
           └─ Margred ferch Thomas (of Iscoed, Ceredigion, Wales - ??) =>
            + Tudur ap Gronwy ( - 1367 Trecasteil, Anglesey, Wales)